The instant invention relates to a new synthesis which for the first time makes it commercially feasible to synthesize triconjugated dienones defined according to the structure: ##STR2## wherein R.sub.1 represents C.sub.1 -C.sub.8 alkyl, phenyl or phenyl methyl and wherein R.sub.2 represents hydrogen or C.sub.1 -C.sub.5 lower alkyl; and wherein the wavy lines are indicative of a "cis" or "trans" juxtaposition of the R.sub.2, methyl, acyl or vinyl moieties about one or both of the carbon-carbon double bonds which process involves the reaction of an acyl halide having the structure: ##STR3## (wherein X represents chloro) with a substituted or unsubstituted prenyl ester having the structure: ##STR4## wherein R.sub.3 represents C.sub.1 -C.sub.5 alkyl in the presence of an aluminum chloride catalyst and a methylene dichloride solvent in order to form the novel intermediate genus defined according to the structure: then dehydrohalogenating the compound defined according to the structure: ##STR5## using an alkali metal carbonate and a dimethylformamide solvent in order to form the novel compound genus having the structure: ##STR6## wherein one of the dashed lines represents a carbon-carbon double bond and the other of the dashed lines represents a carbon-carbon single bond; and then dehydroacyloxylating the compound having the structure: ##STR7## in order to form the compound having the structure: ##STR8## the dehydroacyloxylation step taking place in the presence of an alkali metal carbonate and dimethylformamide solvent; including mixtures of "cis" and "trans" tagetone defined according to the structure: ##STR9## as well as "cis" and/or "trans" isomers of the compounds having the structures: ##STR10## which mixtures are useful in perfumery.
Arctander "Perfume & Flavor Materials of Natural Origin, (1960), at columns 606 and 607, indicates the usefulness of Tagete oil and further indicates that "there is no suitable substitute for crude Tagete oil . . . and once these materials are established in perfume formulas the oil must be precured somehow . . . the main constituent, Tagetone, and an unstable ketone is presumably responsible for the peculiar odor and for the resinification and unstability of the oil . . . ".
Nevertheless, if tagetone is synthesized in substantially pure form via the process of the instant invention a stable useful Tagete oil substitute can be created.
Tagetone has however been previously synthesized, but these prior syntheses are highly expensive and very difficult to carry out in view of the extreme conditions required.
Thus, Adams, et al, "Journal of The Chemical Society" Perkin I, (1975), pages 1741-43, indicates the synthesis of Tagetone by means of reaction of isoprene with isovaleryl chloride in the presence of a stanic chloride (Lewis Acid) catalyst at -78.degree. C. to form a halide which is subsequently dehydro halogenated using lithium fluoride and lithium carbonate in a dimethylformamide solvent according to the reaction sequence: ##STR11##
Also carried out at -78.degree. C. is the reaction between isovaleryl chloride and to a trimethyl silane complex of isoprene in a presence of a titanium tetrachloride catalyst in a methylene dichloride solvent according to the reaction: ##STR12## as disclosed by Hosomi, et al, Tetrahedron Letters No. 5, pages 429-32 (1979).
Garbers and Scott Tetrahedron Letters No. 19, pages 1625-1628, (1976), also discloses the production of "cis" and "trans" ocimenones which are also major constituents of oil of Tagete according to the reaction: ##STR13##
The compounds having the structures: ##STR14## are novel compounds.
There has been considerable work performed relating to substances which can be used to impart (modify, augment or enhance) flavors and fragrances to (or in) various consumable materials. These substances are used to dimenish the use of natural materials some of which may be in short supply and to provide more uniform properties in the finished product.
Tagete-like and floral aromas are particularly desirable in several types of perfume compositions, perfumed articles (e.g., anionic, cationic, nonionic or zwitterionic detergents, fabric softener articles, perfume polymers and cosmetic powders) and colognes.
Tagete and floral aromas and tastes are desirable in connection with augmenting or enhancing the flavors or aromas of smoking tobaccos both prior to smoking and on smoking in both the main stream and the side stream.